Internet vulnerability

Chester Wisniewski, a principal computer research scientist at Sophos, a security company, said that attacks like the one on Dyn “might be the beginning of a new era of internet attacks conducted via ‘smart’ things.”

“There are tens of millions more insecure ‘smart’ things that could cause incredible disruptions, if harnessed,” Mr. Wisniewski added in an email.

It is possible, investigators say, that the attack on Dyn was conducted by a criminal group that wanted to extort the company. Or it could have been done by “hacktivists.” Or a foreign power that wanted to remind the United States of its vulnerability. The answer may not come by Election Day, but the next wave of attacks very well could.